Door lifting and tilting device



March 2l, 1944. R A. SHIELDS DOOR; LI'FTING AND TILTING DEVICE 2 Sheets-Sheet 1 Filed March `5, 1942 March 21, 1944. R. A. sHlELns DOOR LIFTING AND TILTING DEVICE 2 Sheets-Sheet 2 Filed March 5, 1942 Patented Mar. 21, 1944 UNITED STATI-:s PATENT ,OFFICE DOOR LIFTING AND TILTING DEVICE Robert A. Shields, Berwick, Pa., assgnor to American Car and Foundry Company, New York, N. Y., a corporation of New Jersey Application March 5, 1942, Serial No. 433,527

5 claims. ('01. 16-99) This invention relates to door lifting devices in general and in particular to lifting devices used in connection with sliding vdoors on railway freight cars.

The bulk of freight car doors are now equipped with lift devices which operates to lift the doors vertical. With such lifting devices the operator must not only overcome the weight of the door but must slide the sealing edges of the door along the cooperating parts of the door posts. This vertical lifting of the doors will break any ice or rust at the sealing edges but does not in any way relieve the gripping eifect of the sealing edges which in some cases are provided with springing connections to effect a waterproof seal. It has been proposed to lift the freight car doors only at one corner thus causing a slight tilting of the door, but to insure proper closing of the door this lifting of a single cornerV must occur at the forward or closing edge of the door. vWhen the lifting device is located at the forward or closing edge of the door then the upper forward corner of the door is pried away .fromthe door post but the leverage for prying this corner away is greatly reduced due to the extreme distance to the fulcrum point, namely, the trailing or back edge of the door. Maximum efficiency in lifting and tilting of the do'or can be obtained if the leading edge of thedoor can be lifted more than v the trailing edge, irrespective of the direction of the -doors travel; in other words, if the forward edge of the door is lifted more than the rearward edge during closing and the rearward edge is lifted more than the forward edge during opening of the door. AWith the door lifted and tilted as mentioned, the lower forward corner of the door is pried away yfrom the door post during opening and is the rst to contact the door post during closing of the door. It is an object, there,- fore, Aof the present invention to provide a door with lift devices which will tilt the ydoor during lifting and so that4 the leading edge of the door is always lifted a greater amount than thev trailing edge of the door, irrespective of the direction of door travel.

A further object of the invention isthe provision of door lifting devices which will lift and tilt the door in such a manner that the bottom forward corner of the door is the first to leave contact with the door post in opening of the door and also the first to contact the door post on closing of the door. i

A still further object of the invention isthe provision of simple door lifting means which will vautomatically tilt thev door away from the direction in which the door isA to be moved.

A yet further object of the invention is the provision of simple door lifting devices permitting of the most efficient manner of lifting and starting the opening movement of a slidingdoor.

These and other objects of the invention will be apparent to persons skilled in the art from a study of the following description and accompanying drawings, in which:

Fig. 1 is a side view of the lower portion of the door and supporting track with parts broken away to better disclose the mechanism for lift-v ing and tilting the door;

l Fig. 2 is a sectional view taken substantially on line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken substantially online3-3ofFig.1;-'

Fig. 4 is a plan view of the roller carriage;

Fig. 5 is a side view of the lower portion of the door similar to Fig. I but showingthe door in" a lifted and tilted position for opening movement of the door, and

Fig. 6 is a similar view showing the door lifted and tilted for a closing movement of the door. f

Referring nowto the drawings' in detail, it will be seen that the .door is formed with an `angular form front stile 2 and an angular form rear stile 4 joined together by an'angular form bottom rail- 6, to all of which is rigidly attached the door panel sheet. The `angular form of the front and rear stilesis immaterial as is also the exact form of the bottom rail which maybe independent or integral with thedoor panel sheet. 4In the present form, however, the. bottom rail is independent of the door sheet and is formed, ras clearly shown in Figs; 2 and 3, with aninturned bottom flange ID at the lower edge of a verti` cal portion Il. The vertical portion merges `into a horizontal shoulder portion I2 joined by vertical and inclined portions I4 and I5 respectively to a flange I6 (Fig. l), to which the lower edge ofthe door sheetis attached. For convenience in later describing the portion of the door'lift mech-v anism, the forward lowercorner of the Ydoor has been designated byletterA, while the rearward lower corner ofthe door has'been designated by letter B.

Roller'housings' are attached to the door stiles and to the bottom rail to' support the door through suitable mechanism later to be described. Each of the housings are of substantially inverted open box vformation having outer end walls I8, inner end walls 2U, inner and outer side walls 22 and 24 respectively and upperwall 25. The outer end Walls I8, inner -walls 22 and upper or top wall 25 are connected to the stiles and bottom rail of the door, as clearly shown in the iigures. The end walls I8 and 20 are provided with upturned ange portions 26 adapted to rest on the top surface of a door track member 28 connected to the car structure in any suitable manner. The front side walls 24 are provided with slight downward extensions 3i) adapted to overlap the track slightly and prevent inward shifting of the door and housing relative to the track. As clearly shown in Figs. 2 and 3, the inner side walls 22 are Iformed with flanges 32 adapted normally to rest upon the track and also with downwardly directed anges 34 overlapping eliminate the lugs and openings and rely on theA friction between the door and track to prevent movement of the door during -shunting of the cars. It also may be desirable in some cases to let the entire lower edge of the door rest upon the track but these are mere matters of design.

The end walls IB of the housings are provided with projecting ribs forming a trunnion bearing for the Iforward edge 42 of a roller carriage having sides 44 joined together by the trunnion piece and Iby an end upper wall 46, part oi which is depressed in order to clear the operating mechanism later to :be described. The carriage sides are pierced to receive an axle S8 on which is journaled a roller 50. The roller carriage is entirely free of any direct connection with the roller housing and accordingly the roller can be assembled in the carriage and the entire carriage inserted into the housing when the door is lowered upon the track. The inner and outer side walls of each of the housings are pierced to receive a stub shaft 52 (see Fig. 2). The inner end of the stub shaft is of reduced diameter and rotatably mounted in the Side wall 22, while the outer end of the stub shaft is of larger diameter and ro tatably mounted in the side wall 25. The portion of the stub shaft intermediate the bearing portions is squared to receive the hub portion 56 of an operating member held in place on the stub shaft by meansy of a cotter or other device 58.

Each of the operating members is formed with arms 6D and 62 projecting inwardly and outwardly respectively from the hub portion. For convenience in description, these arms are marked 60 and 62 a or b, dependent upon whether they are located adjacent the A or B edge of the door. The arms 62 are spaced apart so as to receive 'therebetween the rollers 50 and so as to bear upon the upper edges of. the side pieces lliv of the rolier carriage. The arms may also be spaced apart but it is preferable that they be joined together-permitting them to bear upon the upper wall 45 of the roller carriage. As clearly shown in the drawings, the stub shafts 52 are formed integral with the lower ends of cranks 6 located outwardly of the outer walis 24 of the housings. It will be seen that the stub shafts need merely to 'be inserted through the hub 5S integral with the operating arms and the Cotter 58 inserted to lock the stub shaft and cranks together and hold them in place in the housing. In the present instance one of the cranks is made long to provide a handle 66 for the operator, while the other crank is made relatively short and connected by a tie bar 68 extending between it and a portion of the crank which is extended for use by the operator.

When the door is in its normal open or closed position the handle 65 is vertical and the arms 60 and 62 substantially horizontal and clear of weight-:bearing engagement with the arms of the roller carriage. When the door is in this normal position its entire weight is supported on the tracks independent of the roller carriages which support none of the door weight. When it is de sired to open the door the handle is grasped by the operator and pulled toward the position shown in Fig. 5. In doing this the operator tends to open the door and the pressure applied while tending to open the door also causes rotation of the operating members and in -such a direction that arms Sila and B2b bear upon the roller carriages forcing them downwardly. Downward movement of the inner ends of the roller carriages will cause them to ulcrum about the axles 48 with the result that the trunnion portion 132 will move upwardly lifting the door. When the parts are rotated as shown in Fig. 5 the arms Sib bear upon the roller carriage nearer the corresponding axle 48 than do the arms Gila. Accordingly, for the same angular movement of the op erating members the B corner of the door is lifted approximately twice as much as the A corner of the door. This higher lifting of the B corner of the door causes the door to be tilted away from the direction in which it is to be moved with the result that the A corner of the door is pulled outward away from the door post with the door as a whole fulcruming about the upper forward corner of the door (not shown). Thus the door is lifted and tilted, with the tilting action tending to tear away the sealing engagement between the door and door post. When the door is open and it is desired to close the same, the operator will pull the handle toward the position shown in Fig. 6, in which case the arms 62d and Elib contact their respective roller carriages with the result that the A corner of the door is lifted a substantially greater amount than the B corner of the door, thus again the door is tilted away from the direction in which it is to Ibe moved. When the door is pulled toward closed position, with the parts as shown in Fig. 6, the A corner of the door will contact the door post rst, then as the operator starts to lower the door the B corner will engage the track preventing shifting of the door along the track and as the A cor'- ner falls into position the'door will 'be cammed into tight sealing engagement with Athe door post. It will be seen from the description of the operation and from the drawings that the A corner of the door is always the iirst to leave Contact with the door post upon opening of the door and the rst to make contact with the post upon closing or" the door. By lifting and tilting the door in the manner shown and described maximum emciency is obtained for the lifting and lowering of the door is combined with a tearing and camming action tending to break or make the seal between the door and door post, thus re; ducing to a minimum the operators effort necessary to open and close the door.

It will be obvious to persons skilled in the art kthat various modifications and rearrangements of parts other than those shown and described may be made but all such modiiications and rearrangements of parts are contemplated as will produce the results described and as will fall within the claims deiining the invention.

What is claimed is:

1. In a lift device for sliding doors having the bottom portion normally resting on a supporting track, the combination of lift mechanism adjacent the lower corners of the door and each comprising, a roller, an axle extending through the roller, a roller carriage rockably carried by the axle, a roller housing secured to the door and substantially inclosing said roller carriage, a projecting ledge in said housing overlapping and engaging one end of said carriage, operating means overlapping the other end of said carriage and being formed with arms engaging said carriage at varying distances from said axle, and means connecting the operating means to shift the same and cause said arms to rock said carriage-s varying degrees to lift and tilt the door.

2. In a lii't device for sliding doors normally having the bottom portion resting on a supporting track, the combination of a roller carriage located adjacent each of the lower corners of the door and pivotally supporting the door during lift of the door, supporting rollers supporting the carriage on the track for rocking movement about the axes of said rollers, and means bearing on said carriage to rock the same about the roller axes to lift the door, said means including levers adjacent each carriage, each lever bearing on the adjacent carriage at a different distance from the adjacent roller axis and so arranged as to lift the leading edge of the door a greater amount than the trailing edge.

3. In a lift device for sliding doors normally having the bottom portion resting on a supporting track, the combination of a roller carriage located adjacent each of the lower corners of the door and pivotally supporting the door during lift of the door, supporting rollers supporting the carriage on the track for rocking movement about Cat the axes of said rollers, a lever located adjacent each carriage and bearing thereon to rock the same about the roller axes to lift the door, each lever bearing on the adjacentcarriage at a difierent distance from the adjacent roller axis and so arranged as to tilt the door in a direction away from the direction in which it .is to be moved,

4. In a lift device for sliding doors normally having the bottom portion resting on a supporting track, the combination of a roller carriage located adjacent each of the lower corners of the door and pivotally supporting the door during lift of the door, supporting rollers supporting the carriage on the track for rocking movement about the axes or" said rollers, a pair of lever arms rcckably carried by the door adjacent each carriage and alternately bearing thereon to rock the carriage about the roller axes to liit the door, and operating means to simultaneously rock said lever arms and bring one arm of each pair into bearing Contact with the adjacent carriage but l at different distances from the adjacent roller axis to thereby tilt the door during lift.

5. In a lift device for sliding doors normally having the bottom portion resting on a supportu ing track, the combination of a roller carriage located adjacent each of the lower corners of the door and pivotally supporting the door during lift of the door, supporting rollers supporting the carriage on the track for rocking movement about the axes of said rollers, a pair of lever arms rockably carried by the door adjacent each carriage and alternately bearing thereon to rock the carriage about the roller axes to lift the door, and operating means to simultaneously rock said lever arms to bring one arm of each pair into bearing contact with the adjacent carriage, the lever arm adjacent the leading edge of the door bearing on the adjacent carriage at a point closer to its supporting roller axis than the point at which the lever arm located adjacent the trailing edge of the door bears on its adjacent carriage.

ROBERT A. SHIELDS. 

